Organizations rely on the computing infrastructure to provide a broad array of services. To meet the demand to employ, maintain, and grow these services, IT organizations must continue adding new servers to increase computing capacity. However, as a consequence of purchasing new servers, organizations based growing server sprawl that presents challenges that include rising costs, decreasing manageability, and decreasing business.
IT budgets are continually scrutinized by corporate managers and shareholders. As a result, emphasis has been placed on cost take out to reduce these ever expanding IT budgets.
One solution to server sprawl and increased IT budgets is virtualization. Virtualization makes it possible to package a complete server including hardware, operating system, applications, and configurations, into a portable virtual machine package. Multiple virtual machines can then be run simultaneously and independent on a single physical server. This is possible because a virtualization layer provides each virtual machine a complete virtual hardware configuration while managing the sharing of server resources among virtual machines. With virtualization, each workload that previously required a dedicated physical server can be placed in a virtual machine, making it simple to consolidate multiple workloads onto each physical server.
Server virtualization has been gaining more market share as a viable way to provide cost takeout. Products, such as VMWare™, by the EMC Corporation, and Virtualization Engine™, by IBM, consolidate numerous physical servers into a single host server with scores of guest operating systems running under a virtual server.
Despite improvements in cost and efficiency provided by virtualization, the need to share information between guest virtual machines running on the same host system has not been addressed. File and information transfer between consolidated server systems still happens historically and typically over the LAN or WAN. This fact has not changed, even though some of these virtual images now physically reside on the same host server.
The current state of information transfer between guest virtual machines residing on the same physical server is illustrated with reference to FIG. 1. Each guest virtual machine operating system is encapsulated into file 101 stored in host operating system storage 103. Each operating system image 101 has associated therewith image storage 105.
In FIG. 1, there is illustrated the transfer of a file 107 from image storage 105c to image storage 105b. File 107 may be transferred using any number of well known file transfer protocols, such as FTP, Windows File Sharing, CIFS, NFS, SCP, and others. Operating system image 101c passes file 107 to a virtual protocol stack (not shown) provided by the virtualization infrastructure, and thence to a LAN or WAN 109. File 107 is received at the host, passed back through the protocol stack, and then to operating system image 101b, and then to image storage 105b. Thus, network resources are consumed simply transferring file 107 from one location and host operating system storage 103 to another location in host operating system storage 103.
As long as the virtual images are located on the same physical host server, there is, in theory no requirement or limitation to move information outside of the virtual image over a LAN/WAN into another virtual image located on the same physical host server. Additionally, using traditional file transfer technique consumes LAN/WAN network resources unnecessarily. It is commonplace to find LAN and WAN bottlenecks or high utilization, and removing unnecessary consumption of this resource presents a significant saving in LAN cost. The final drawback for existing solutions is that the transfer of data over the LAN/WAN link is time consuming and typically slower than a direct disc to disc transfer within a bus. A typical LAN connection might entail a 100 mbps Ethernet topology. A fast disc sub system, shared by two or more virtual servers is loaded only by the speed at which the disc spins and the speed at which the drive heads can move. This can typically range between 150 mbps to over 200 mbps, the difference depending on the disc technology used. In these cases, the transfer is more than four times slower using existing known technology. For large data transfers, which are the typical, this can translate into significant time delays.